Reported Cases of Lyme Disease in Minnesota by Month of Onset
Exposure to blacklegged ticks (deer ticks) and Lyme disease in Minnesota occurs primarily from May to July, and again in the autumn, when people are outdoors and ticks are actively feeding.
The majority of cases occur in June, July, and August, peaking just after the mid-May to mid-July period when the nymphal deer tick is feeding. This lag is due to the 3-30 day period between an infected tick bite and the start of signs and symptoms.
- Reported Cases of Lyme Disease in Minnesota by Month of Onset 1998-2008 (PDF: 32KB/1 page)
This bar graph shows reported cases of Lyme disease by the month of onset.